Automatic telephone system



July '1, 1930.

c. GILLINGS AUTOMATIC TELEPHONE SYSIEI Original Filed Nov. 1. 1922 4 Sheqt-Sheet 2 Inuen nr-- Charles Gillin s July 1, 1930. c. GILLINGS AUTOMATIC TELEPHONE SYSTEI Original Filed Nov. 1. 1922 4 Sheets-Sheet 3 lama-IE? Charles Gillin s Patented July 1,1930

UNITED l ST TES ,cunnnns er'nnmes, on Lrvnnroon. nncrinnunssreuon nr .i ssremvrnn'rs,

TO auromarrc nnncrnrc rumor CHIGAGQ, rumors, A conronerron on, DELA- PATENT orrics AUTOMATIC 'rnnnrnonn' srsrn vr flriginalapplication filed November 1, 1922, serial nojseaese, now mam; 1,705,462, dated Mai-a 12,

1929, andin Great Britain. December 17, 1921 "No. 292,493. i

" The present invention concerns improve merits inor relating to telephonesystems employing automatic 1 switches, and nore particularly to improvements in that type of system which employs aregisterdevice for storingup impulses and thereafter controlling the operation: of automatic switches to complete the connection. 1 Such registers have been largely used in connection with what'are known as revertive control systems, that. is

to say, systems inlwhichiseriesof impulses correspondingto thesettlng of the registers are sent back from the selector switches succes'sively as they operate to complete the connection. i One of the features of the present disclosure is the application of such registers to automatic telephone systems of the Strowger or like type, in which the impulses are emitted from the register to control the operation of the selector and connector switches. Such registers are particularly advantageous in large net-works where they facilitate the change of subscribersnumbers, and, also facilitate trunking changes whichmay be necessary.

Another feature i the 1 present disclosure relates to an improvedregister and V translator for use for instance in convertlng large net-works from manual to automatic working, in which the names of themanualexchanges are retained, and for this reason the number holes of the dial are given alphabetical as wellas numerical designations and the subscriber first'dials a number of series of impulses corresponding to the first letters in the name of the exchange, usually the first three letters.

Accordingly, a registering device iscprovided adapted to respond to a plurality of series 'ofimpulses, usually'S, andtohave a separate and distinct setting position for each exchange or group of lines in. the net-- I work, so that by a suitable translating ELI":

rangement any desired series or combination of series of impulses-may be generated to route the call tothe desired'exchange,

The main object of the present invention which is a division of my applicatlon Serial N0. 598,239,filed November 1,1922, (issued Divided andthis application iiledJ'uiy 13 192 8; Seria1- A further object is to utilize the same registering apparatus for controlling the opera- 1 tion of the switching apparatusand for coni trolling thevariable assessing apparatus.

Other objects and features will appear as the perusal of the description progresses.

The invention will be better understood by referring to the accompanying drawings, in

whichFlgs; 1, 2, 3,4, and illustrate byway of example a complete arrangement for carrying theinvention intoeffect.

Referring to Figures lto 5, it will be assumedthat it is desired to establish a connection' betweena subscriber at substation A The sub-l nection by means of its wipers 11, 12, and

whichin the usual manner initiates the op- 7 eration. of the line switch G to establish con 200 with an outgoing primary trunk line 13, f

14. On the switching relay 15 of the line switch operating, a circuit. will be completed for the line relay 16 of a group of relays associated with the trunk line selected, as

follows battery, relay 16,- contactl'T, upper winding of relay 18, line 13, wiper 11, substa- I tion A, wiper 12, line 14,,contact 19, relay 16 to earth. Relay 18 is so designed that it can only energize when both its windings assist each other, which only occurs when the currentthrough theispeaking leads is reversed,

contact 20'completes a circuitfor relay:21.' Relay=21 energizes and at its contact 22 completes a circuit for the switching relay 23 in series with rotary magnet 24: of a rotary switch F, while at its contact 25 it connects the, test wiper 26' of the switch F to a junctherefore only relay 16 energizes and at its 5 various devices operated as long as the relay 37 is operated. The subscriber at A will now hear the dial tone'from transformer 46 over magnet 45, contact 44, wiper 43, relay 42, con-. tacts 34, 41, condenser 47, lead 14 and his in,

strument, and will operate his impulse sender 39 inaccordance, with the first series of impulses i. e.,the first digit of the exchange. code, the relay 16,- thereby releases a number of times and at its contact 40 completes a circuit as follows :earth, contact 40, contact41, contact 34, series relay 42, Wiper 43, contact 44, magnet 45, winding of dial tone-transformer 46 to battery. The 'magnet45 and series relay 42-respondto this firstseri'es 'of impulses, the magnet 45 to step the Wipers 48 to 50 of minor'switch MS anumber o-f'steps in accordance with the digit dialled while theseries relay'42 at contact 51 completes'a circuit for slow release relay '52 which energizes and at its contact 53 prepares a circuit for the magnet 54 of the master digit switch MDS: this circuit is completed at contact 55 after relay 42 has deenergized'at the end of afirst series of impulses', so that the wiper. 43 is advanced to contact 56. The next series of impulses thereby passes'over the same circuit to wiper 43 whence it passes over contact 56 and wiper 49 to the vertical magnet 57 of a Strowger switch SS having two directional movements The'Strowger switch SS represents one of. a number, usual"- ly 8 or 9, connected with the diflerent contacts accessible to the Wipers 48'to 50, the vertical magnet responds to raise the wipers to the level corresponding to-this series of impulses on the completion of which the magnet 54 has its circuit completed as before and steps the'wiper 43 to the contact 58 so that the impulses nextieifect the opera-' tionofthe rotary magnet 59 over the wiper 50. The wipers of the switch SS are thereby rotated tocertain contactsin the row. When this occurs, a circuitis completed for a code relay CR corresponding to the exchange required connected to one of the contacts selected, this circuit maybe traced'from earth, wiper 60, contact 61, lead 62, relayGR to battery. Relay CR, therefore, energizes and connects earth at contacts 63 and 64' to contacts 65 and 66 of two distributing frames 7 NS III, NS IV are operated in accordance with these last three digits and serve to store the number of the wanted subscriber in the exchange determined by the first three digits. The distributing frames DF I, DF II consist, of ten terminals on one side and a number of terminals corresponding to the number of code'relaysprovided on the other side. The ten terminals of the distributing frames DF I, and DF II are connected to corresponding contacts on sender switches SS I and SS II respectively. Similarly, the ten contacts of the switches NS I to NS IV swept over by the wipers 78 to 81, are connected to the ten contacts of other sender switches SS III,- SS IV, SS V, SS VI. 'Whenthe code relay-CR is operated, a circuit is prepared through its contact 82 which may be. traced as follows: earth, contact 82, lead 83, common to all the code relays, contact 84, lead 85, contact 86 (Fig. 5), lower winding ofrelay 87,.lead 88, contact 89 (Figure 4), contact 90, lead 91, contact 92, controlled by the impulse cam 94. The impulse cams 93 and 94 are mounted on a common shaft and while the cam 93 isadapted to generate impulses correspcnding to the impulses generated by a dial switch or'impulse sender of the usual type, the cam 94 is adapted to close a circuit only between impulses. This insures that only the correct impulses are generated and that'no'circuit is completed at an unsuitable time. As soon, therefore, as the cam 94 closes contact 92, relay 87 energizes and at its con-. tact 95 completes a locking circuit for itself to the lead 85, and earth on contact 82 as previously described. At contact 96 a circuit is prepared for impulse relay 97, which energizes each time the cam 93 closes the contact 98-. Relay 97"atcontact 99 thereby periodically opens a circuit across the leads 100 and 101, which leads extend via contacts 32 and 33 (Figure 1) wipers 102,103, leads 28, 29, contacts l04, 105 to line relay of selector EI, which relay is not shown, as it forms no part of the present invention. It willthus be up preciated that each time contact 99 is opened, the vertical magnet of the selector E responds and raises the wipers one step. Relay 97 at contact 106 also completes a circuit over lead 107, contacts 108 to 112 (Figure 4) magnet 114, to battery. Magnet114 of sender switch SS I, therefore, responds with the vertical magnet of the selector switch E until the wiper 115 engages thev contact'116 ccnnected tothat contact 117 on the frame DF I to which the contact 65 selected by the code relay CR has been connected. hen this happens, a circuit may-be traced as follows: earth, contacts 64, 65, 117,116, wiper 115, relay 118 to battery. Relay 118 energizes and at contact 112 opens the circuit of magnet 114, which thereupon comes to rest, at contact 84 disconnects earth from lead85, therei by releasing relay 87 and preventing the furnumber being determined entirely by the concompleted until contact 123 is closed which a will onlytake-place after theneXt switch nection made'at the distributingframe DF 1. At contact 119, relay 118 locks itself energized over a circuit whichmay be traced'as follows: earth, battery, relay .118, I contact 119,'lead 38 which was earthed by relay 37, and at contact 119' connects the grounded lead 38 to the restoring bank 185,,whereupon the switch is automatically advanced to normal by magnet 114, which interrupts its own circuit at-contact 113; If the number switch NS I has .left its normal position, olfnormal contact will be closed and a circuit prepared as follows: earth, contact 70, contact 120, relay 121'to lead 122. .This circuit is not to respond to the train of impulses has been taken into use. .The selector E on being raised to the desired level, rotates automatically to find an idle line, assumed to be the line 124,125 leading through repeater R of well'known construction, and of-which only the polarized relay 126 is shownflto 'aselector E in another exchange. On the selector E being talren intouse, the relay 1 138 of the selector E energizes to switch through and a momentary circuit iscompleted as follows; until the release relay 127 falls back, which it does shortly afterwards earth, battery B resistance 128, contacts 129, 130, 105,1eads 29, contacts 103, 33,1lead 101, contact 134, to relay135 and normal battery to earth. The battery B has its negative pole] connected to earthiinstead of its positive pole, which is the usual convention, and,therefore, an increased current will'flow through the relay 135, thislirelay isfsoadjusted that it will not respond to normal currents o'n the xline, but will respond tothe increased currents. Belay 135, therefore, responds during the energizetion' 'of the release relay and at contact 136 completes a locking circuit foritself through contact 137 .to earth. The closure er contact 123 completes the circuit previously described and relay .121 energizes, and at ma tact 122, completes the circ'uit'betw'een. the

leads 88 and 91, opened at contact 89 on relay 118 energizing. Asearth was connected to lead from lead 38, through contacts 140,

141, itwill be appreciated thatconditions are now the same as they were when theoperation of switch SS I was started. 'Relay 87 energizes, as also relay 97 to performa similar function, relay 97 this time causingthe operation of thevertical magnetofselector E and of the magnet/142 ofsender switch SSII, the circuit of this latter'magnet" being completed through contact 143. This operation continues until wiper 144 engages the contact selected by the connectionat the distributing frame DFIIwhen relay 143 is energized. This relay operates in a similar mannerto relay 118 and for that reason no further description need be given of the opcrating circuits, the selector E is operated to the re uired level as determined by the switch S8 II, and in that level hunts for an idle trunk line passing through the re eater. R toza third selector E 'Repeate'r 2 and select-or E are identical'in construction vwith those previously described," and when E is taken into use, a booster impulse is transmitted and'repeated at R lay-means of relay 132 and battery B and contact 133 to cause the reenergiz'ation of relay 135. Relay132 is adjusted similarly to relay 135,'then ifthe off normal *c-ontact146 is closed, the relay 147 will energize and relays 87 and 97 will operate as before-described, the number of impulses generated being now controlled by SS III. The third selector. operates tothe required level and selects an idle fourth selec tor E The booster impulse is then repeated 'over the lower talking conductor to cause the operation of relay 135 when the cycle is completed and the succeeding impulses are sent out in a similar manner under the con trol' ofbS II-SS- V, and SS VI, successively.

The connector H responds to the last two impulses and as there is no trunk hunting operation between these impulses, it is sufli-k 'cie nt toarrange that the relay 148' is some- ,what slow to pull up,ther'eby insuring that the necessary pause takes place between the transmissionof these last two series of impulses without'requiring the transmissionof aspecial boosterimpulse. on the termination of the transmission of the last series of impulses, the relay 149 energizes and, besides performing the functions previously described "with relation to relay 118, at contact 152 connectsleads' 153 and 154 together. By this operation, a 'circuit is prepared as follows: earth, contact 155, lead 153, contact 152, lead 154, contact 74,wiper 43, relay42, "contacts 34, 41', lead 30, contacts 157, 158, relay 159 to battery. This circuit includes 1 At 'coi1tact 162 an impulse circuit is completed which may betraced as follows: earth,

battery, magnet 163 of the meter switch MR,

contact 164, contact 162, lead 31, contact 35,

wiper 48, wiper 165, contact 166, lead 167,

contact 168 controlled by the three point cam 169. It should be here explained that the cams 156,170, 171, 169, 172, 173 are arrangedon the same shaft, the pickup cam 156 closing its spring first followed by thecams 171, 169, 172,.and 173,. generating respectively 4, 3,2, 1 impulses ina cycle and finally by stop cam 170, which serves to render further iao impulses ineffective; Further, .as the register controller is located at the outgoing exchange andthe contact 166 is representative of the wanted exchange, it is possible to accurately determine the charge to be made for a connectionand for this reason it is assumed for tacts155, and responds three times over the circuit described and steps the .wiper174 to third contact. The stop cam 170 then closes contact 175, completing acircuit as follows: earth, contacts 175, 176, 177, relay 178 to battery. Relay 17 8 energizes and at 164 opens thecircuit of magnet 163, at contact 179 closes a-locking circuit for itself to the release trunk conductor 180, and at contact 181 removes earth from the contact 182 which had maintained relay 21 energized after relay 16 had been disconnected at contacts 17 and 19. Relay 21 then deenergizes and at contact 22 opens the circuit of relay 23, which, accordingly, deenergizes and frees the impulse register. The opening of contact 22 also causes the release of relay 37, which falls back and at. contact 194 closes a circuit for release magnets 192, 190, and 191 of switches MDS, MS, and SS, respectively, which thus restore to normal. Relay 37 at contact 193 connects earth to the lead 151 to releasethe switches NS I to NS IV.

At the connector H the ringing had been initiated in the usual manner and the called subscriber rung. On his response, the back bridge relay (not shown) of the connector II energizes and reverses current over the trunk conductors 124and 125, thereby energizing the polarized'relays' 126 of the repeaters to disconnect the relays similar to 132, and further to energize the relay 18. Its two windings have now so energized as to assist each other. Relay 18 does not energize immediately, but only when the start cam 196 has closed the contact 197. When this occurs, a

circuit is closed for the meter M which may be traced as follows: earth, contact. 198,

. I wiper 174, in third off normal position, contact 199, wiper 200, contact 201, meter M to.

battery. The meter, therefore, is energized three times by the three point cam 202 when a circuit is closed by step cam 204'as follows:

earth, contact 203, contact 205, release magnet 206 to battery. The switch MB is, therefore, restored to normal and no further impulses can be generated. The meter has therefore been operated in accordance with us the charge for the connection. It will thus be appreciated that the first of the digits of the subscribers number have been stored on a register, the first three digits have been converted .into two digits according to the impulses required, to reach the desired exchange the remaining impulses have been generated in sequence andthe call set up, and

metering effected on the response of the called subscriber.

A time alarm relay TA isprovided to prevent an impulse register being held up unduly, its circuit is completed through contact's207, 208 when relay 37 is energized. Relay TA is slow to energize, but quick to restore and is so arranged that if a predetermined time has elapsed between the instant that relay 37 energizes and the subscriber commences to dial or a similar delay occurs between successive impulses, as determined by'the energization of relay 42,-a circuit will be completed from earth, through contact 209,."relay 42, contacts 34, 41, lead 30, contacts 157, 158, relay 159 to battery. Relay 159, therefore, energizes and brings about the disconnection of the register switches so that these may-be taken into use for another call." The subscriber will not then get his dial toneand can only get this by hanging up his receiver and initiatinga fresh call. As the number of register sets are limited, it is important to insure that these are not taken into use except when required.

. It'will be noted that in the regular controller set shown in Figure 4, it is necessary to provide contact positions for every possible combination of the three digits. This approximates 1,000 positions and would necessitate'the use of one minor switch and Strowger switches. Inpractice, the whole 10 are notrequired, usually 8 or 9 being sufficient, but in any case a much larger number of contact positions must be provided than are required for the number of exchanges in a net-worlnas inmost cases, there would be less than 100 exchanges in a network and sets responsive to a plurality of digits and having a distinct setting for each oifice in a vmulti-oilice net work are provided, and 1n which impulse sending apparatus is governed in accordancewith the setting of the register sets to transmit directive impulses to the switching apparatus, means controlled by said register sets for also governing the charge assessed against calling subscribers in accordance with the respective destinations of the calls.

2. In an automatic telephone system, trunk lines over which connections are to be extended from calling lines, registering apparatus common to said trunk lines, means controlled from a calling line for setting the registering apparatus in accordance with the line in accordance with the destination of the call,registering apparatus common to a plurality of trunk lines and operable from calling lines in accordance with the destination of calls, and means for setting said'devices in accordance with the setting of the common registering apparatus.

4. In a multi-oifice telephone system, trunk lines in one ofi ice over which, connections originated in such office are to be extended,

means individual to eachtrunk line for con- I trolling the assessing of a charge againstcalling subscribers using such trunk lines,

and controlling means in said one oflice com.-v

mon to a plurality of said trunk lines for governing the setting of said individual means.

5. In a telephone system, trunk lines over which connections from calling linesto called lines are to be extended, adjustable means individual to each trunk line for controlling the assessing of a charge against a calling" subscriber using *such trunk line, and registering apparatus common to a plurality of trunk lines and arrangedtobe set over any trunk line, over a circuitpath independent of the connection extended from such trunk V ance with the location of the called line,and

line toward a called line,to control the adjustment of said means. v

6. In a telephone system, a trunk line over which connections areto be extended, means for extending a telephone connection to said trunk line and for subsequently further exs a charge against the calling line commensuratewith the location of the called line.

In witness whereof, I hereunto subscribe my name this 25th day of June,'A. D. 1928. CHARLES GILLINGS.

tending the. said connection over, the trunk line toward a called line, registering apparatus common to said trunk and other trunk lines, means for-extending a branchconnec tion from said trunk line to the common ap paratus and for settingthecommon apparatus in accordance with the destination of a call, a charge accessing, deviceon said trunk line, and means for setting saidfidevice over said branch connection in accordance with said common registering apthe setting of paratus; v

' 7. In a telephone system, means r for 'x tending atelephone connection from-a calling line to a called'line and for extending "a branch connection fromthe mainconnection, I registering apparatus set over said branch connection from the callingline in accord} means controlled over said branch connection from said registering apparatus for assessing I l 

